Disazo dye from dihydroxy benzidine and process therefor



'Petented July i2, 1949 UNITED STATES APATisYiN-T -oFFIcE A comets) y nrsazo niza mou nmronoirr aan raocnss 'runnnron l l Hans Basel, and Willy' Widmer, mygvitnerland. 'mignon to Ollla Limited,

mingen,

Boli

BaaeLSwltla'laniaSwisorm No Drawlnx.

ilcn February 28, 1941. 8e-

According to this invention valuable asymmetrical diano-dytui'is are .made by coupling tetraaotised 8 :3' -dihydroxy-i 4*-diamlnodipheny1 with coupling components, and conducting the irsi coupling operation in a reaction medium having a pH value ranging from that of an acetic acid medium to that of a medium rendered aikaline with an alkali carbonate and the second coupling operation in a reaction medium having a. pH value higher than that of the medium used in the urst coupling operation.

The rst coupling operation may be conducted. depending on the choice oi the first coupling component. ior example in a weakly acid or neutral medium or in a medium rendered alkaline with an alkali bicarbonate or alkali carbonate. The second couplingr operation is conductecLtor oxample. in a neutral medium or a medium renderedV alkaline with an alkali bicarbonate or ammonia or a caustic alkali, provided that the medium is 20 more strongly alkaline than that used in the rst coupling operation. Thus, for example,the ilrst coupling operation may be conducted in an acetic acid medium and the second coupling operation in a medium rendered alkaline with an alkali carbonate, or the first coupling operation in a medium rendered alkaline with an alkali carbonate and the second in a medium rendered alkaline with caustic alkali. l

In the process ci the invention there come into consideration as mst and second coupling componente those which owe their capacity for coupling to s. reactive aromatic atomic grouping or to a reactive kam-methylene group. The coupling components may contain groups importing solubility, such as carboxyl, sulionamido or sulionlc acid groups. There come principally into consideration, for the mst and also for the second coupling operation, components which lead to dye- 4g as a second coupling component a compound stuils capable of forming heavy metal complexes, and among such components especially those which contain in ortho-position to the coupling position a group ior example, a hydroxyl group. capable oi' forming heavy metal complexes in conJuncton with the hydroUl group of the diacocomponent. Especially valuable products may be obtained by using as the xst coupling component one which contains a group imparting solubility. i'or example. a. sulfonio acid `group, and

as the second coupling component, on the other 5c 80 NIN! 4,5 an alkali carbonate, for example. n

. 2 hand, one which is tree f roxn groups imparting solubility auch as carboxyl and sulfonio acid croupe. In this-connection there-'are suitable,

= for'exampie, the following coupling components: .As rst coupling components: l-(sulfoaryD-S- pl) il-methyl-o-pyraaoloneg-lza-dlphenyl 5 pyrazolone; auchv as l.-(3'sulio-B'chlorophenyll 8(4"chlorophenyl) 6 pyraaolone; hydroxyna'phtha'lene sulfonic acids capable oilcmipling in 4ortllo-position with respect tothe hydroxyl group, such as 1:3-, `1:4-, 1:5. -2:6- 'or zz-'l-hydroxynaphthalepe -sulionio acid; and amino-hydroxynaphhalene sulionlc acida capable of coupling in ortho-positionwith respect 'to the group. such as -amino--hydroxynaphthalene-'I-sulionic ocio, z-anuno 8- hydromaphthalene-E- 'sulfcnle acid and substitution products thereof. As second coupling components: Acetoacetic acid arylld'es auch astlc acid anilide; pyro.:- olone compounds auch as 8methyll-5-pyraaolone. l-phenyl-s-methyl-E-pyrazolone and li8nitro phenyl) -3 (4"-chlorophenyll -6-pyrazolone; hy-

thalenes capable oi coupling in orthopocition'withrespecttoahydroaylsroupsuchas 'aphthalena 2:6-phth.- lene. il- 4clroxy--mothoxyuaphthalene z-anuno- 'i-hydrownaphthalene 4 2-(p-hydroxyethyleminol-i-hxdroxynaphthalene, 5:8-dichloro-1-hyene and the like,

g5 TheA process of the invention may leed to @Specially valuable resiuts when there is chosen as a rst coupling component a l-(eulioaryl) -3- methyl--pyraaolone and the rst coupling operation is oonductedin an acetic acid medium, and

which ls free from sulionic acid groups and contalus a. -CHe-CO- group rendering coupling possible and the second couplinz operation conducted in a medium rendereqalkal u car.. bonate. As ilrst coupling comp l nts for this purpose there comeinto co ex-ation, for example: -ihsuli'olahenA or 1-(4'n-suliophenthis purpose there are advantageously used those which are stable towards alkaline baths, such as complex copper tartrates and the like.

Certain asymmetrical disazo-dyestuis obtained from tetrazotized 3 3-dihydroxy4:4'-diaminodiphenyl have been described in the literature (see for example, British Patent No. 102,881), but the first and second coupling operations are always carried out under practically the same conditions of pH value. 'Ihis process has the disadvantage that only in very few cases it is possible to obtain a satisfactory result. With most combinations of diazo components and coupling components in this procedure non -homogeneous products are obtained, because in the iirst coupling operation a part of the tetrazo-compound reacts to form the symmetrical disazo dyestui. On the other hand the process of the present invention leads to a considerable improvement in this respect in that it is practically always possible to obtain products in a homogeneous condition. Moreover, it is possible by the present invention to achieve combinations which could not be produced by the known process.

The following examples illustrate the invention, the parts being by weight:

Example 1 21.6 parts of 3:3'-dihydroxy4:4'diaminodi phenyl are tetrazotized in the usual manner, and the tetrazo-compound is neutralized and separated by ltration and introduced into a neutral solution of 25.4 parts of 1-(3'sulfophenyl)3 methyl--pyrazolone. 'I'he whole is stirred at room temperature until the tetrazo-compound can no longer be detected in the reaction mixture which contains the monoazo-dyestui. A solution of 18.5 parts of acetoacetic acid anilide in 80 parts of water and 14 parts of caustic soda solution of 30 per cent. strength is then introduced, and stirring is continued for a few hours until coupling is complete. The dyestui is worked up in the usual manner and dried. It dissolves in Water With a brownish red coloration and in caustic soda solution with a blue-red coloration, and dyes cellulose fibers from a neutral or weakly alkaline bath brownish-red tints, which upon treatment with copper salts become brownish blue-red tints which are fast to light and washing.

Example 2 21.6 parts of 3:3dihydroxy4:4'-diaminodi phenyl are tetrazotized in the usual manner, and the tetrazo compound is neutralized and separated by filtration, and introduced into a solution of 25.4 parts of 1-(4'sulfopheny1)-3-methyl-5- pyrazolone rendered weakly acid with acetic acid. The whole is stirred at room temperature until the monoazo dyestuil is formed, a solution of l1 parts of S-methyl-S-pyrazolone in 50 parts oi water, 14 parts of caustic soda solution of 30 per cent. strength and 5 parts of calcined sodium carbonate are then added, and the whole is stirred until coupling is complete. The dyestuif is worked up in the usual manner and dried. It dissolves in water with a blue-red coloration, and dyes cellulose fibers from a neutral or weakly alkaline bath blue-red tints which upon treatment with copper salts become bluish Bordeaux tints which are fast to washing and light.

By using in this example 27 parts of 1-(8'sulfo 2naphthyl)-3-methyl-5-pyrazolone, instead of the aforesaid quantity of 1-(4-sulfophenyl)3 methyl-E-pyrazolone, there is obtained a dyestuf! which yields on cotton after-coppered dyeings of good fastness to washing and light and which have more bluish tints.

Example 3 The tetrazo-compound obtained from 21.6 parts of 3 :3 -dihydroxy-4 4-diaminodiphenyl produced as described in Example 1 is introduced into a neutral solution of 25.3 parts of 1-(4' chloro 3 carboxyphenyl) 3 methyl 5 pyrazolone, and the whole is stirred at room temperature until the monoazo-dyestuif is formed in the reaction mixture. A solution of 18.5 parts of 1-phenyl-3-n1ethyl-5-pyrazolone in 80 parts of water and 14 parts of caustic soda solution of 30 per cent strength are then added, and the whole is stirred until coupling is complete. After separating and drying the dyestui'l there is obtained a black-brown powder which dissolves in water with a brownish red coloration and in caustic soda solution with a blue-red coloration, and dyes cellulose fibers brownish blue-red tints, which upon treatment with copper salts become Bordeaux tints which are fast to washing and light.

Example 4 21.6 parts of 3:3dihydroxy-4:4diaminodi phenyl are converted into the tetrazo compound in the usual manner. The latter is isolated and introduced into a neutral solution of 25.4 parts of l- (4'sulfophenyl) -3-methyl-5-pyrazolone. When the monoazo-dyestuif is formed, a solution of 13.5 parts of barbituric acid in water and then 16 parts of a caustic soda solution of 30 per cent. strength are added, and the whole is stirred for a long time until coupling is complete. The dyestuil is worked up in the usual manner and dried. It dyes cellulose fibers brown-red tints, which upon treatment with copper salts become Bordeaux tints which are fast to light and washing.

Example 5 21.6 parts of 3:3'-dihydroxy4:4'diaminodi phenyl are tetrazotized in the usual manner, and the tetrazo-compound is neutralized and separated by filtration, and introduced into a solution of 22.4 parts of 2-hydroxy-naphthalene-6- sulfonic acid in parts of water and 30 parts of potassium carbonate. The whole is stirred at 1li-15 C. until the tetrazo-compound can no longer be detected in the reaction mixture containing the monoazo-dyestuii. A solution of 16 parts of Z-hydroxy-naphthalene in 60 parts of water and 6 parts of caustic alkali are added, and the coupling is completed by slowly raising the temperature to 30 C. in the course of 24-30 hours. The dyestuff is then Worked up and dried in the usual manner. It dissolves in water with a violet coloration and in caustic soda solution with a blue coloration, and dyes cellulose fibers violet tints which upon treatment with copper salts become bluish violet tints which are fast to washing and light.

By using, instead of Z-hydroxynaphthalene-S- sulfonic acid, 2hydroxynaphthalene4 or 'lsulfonic acid or l-hydroxynaphthalene-fior 5- sulfonic acid there are obtained somewhat more bluish tints. A similar dyestuf! can also be obtained by using in the second coupling operation, instead of 2-hydroxynaphthalene, 2-hydroxy-'l-aminonaphthalene or Z-hydroxy-'l-hydroxyethylaminonaphthalene, for example.

IThe appended claims are directed to the subject matter of the first paragraph of this example.

second place in, a medium rendered alkaline with Number a caustic alkali with Z-hydroxynaphthalene. 2,193,438 HANS MAYER. 2,241,796 WILLY WIDMER. 2,384,419 5 2,404,198 REFERENCES CITED 2,424,006 The following references are of record in the Zgg'gg'z file of this patent: 2' 5 7 UNITED STATES PATENTS 10 Number Name Date Nurgeal 1,210,751 Anderwert et al Jan. 2,v 1917 410192 1,292,385 Anderwert Jan. 21, 1919 232510 1,457,235 Stusser May 29, 1923 1,889,732 Stusser et al Nov. 29, 1932 18 Nan'i` Date Taube et al Mar. 12, 1940 Taube et al. May 13, 1941 Fleischhauer Sept.. 4, 1945 Straub et al July 16, 1946 Straub et al July 15, 1947 Straub et al Sept. 9. 1947 Straub et al Sept. 16, 1047 FOREIGN PATENTS Country Date Great Britain Jan. 4, 1917 Great Britain May 14, 1934 Switzerland Aug. 16, 1944 Certificate of Correction Patent No. 2,476,259 July l2, 1949 HANS MAYER ET AL.

It is hereby certified that errors appear in the printed specfcetion of the above numbered patent requiring correction as follows:

Column 2, lines 9 and 10, for the Word pyrazolone read pyrazolones; lines 11 and 12, for pyrazo1one; read pymzolones,; line 31, for 2amino read 2-am1lno; column 8, line 26, for pyrezoline read pyrazolone; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 3rd day of January, A. D. 1950.

THOMAS F. MURPHY,

Assistant Uommz'aazoner of Patents. 

